CN101142521B - Particle for display medium and information display panel using same - Google Patents

Abstract

Disclosed is a particle for display medium which is used in an information display panel wherein information such as an image is displayed by sealing at least one display medium between two opposing substrates at least one of which is transparent and moving the display medium through application of an electric field. A material having electrical characteristics of a semiconductor is arranged on the surface of the particle. Since such a particle for display medium has a surface having electrical characteristics of a semiconductor, the surface charge of the particle can be stably maintained. Consequently, there can be obtained a information display panel wherein the display state of information such as images is stable.

Description

Display medium is with particle and use the information display panel of this particle

Technical field

The present invention relates to display medium with particle and use the information display panel of this particle, above-mentioned display medium is used at the display medium of enclosing between two relative substrates more than at least a with particle, display medium is applied electric field and make display medium move the information display panel of information such as display image, at least one substrate is transparent in the wherein above-mentioned opposing substrates.

Background technology

In the past, the instead information display device of LCD (LCD) of the favourable information display device that causes technology such as color mode, hot mode, double-colored particle rotation mode with electrophoresis mode, electricity was proposed.

These prior aries are compared with LCD, have can obtain little near big field angle, the power consumption of common printed matter, have an advantage such as memory function, therefore consider its technology as the information display device that can be applicable to cheapness of future generation is just being expected to promote to aspects such as the demonstration of portable terminal client information, Electronic Paper.Especially recently proposed and to have made microcapsules by the dispersion liquid that dispersed particle and coloring solution are formed, and it has been configured between the opposing substrates and the electrophoresis mode that constitutes, and expressed expectation.

Yet, in the electrophoresis mode,, thereby exist viscous resistance to cause the slow problem of response speed because of liquid owing to particle moves in liquid.In addition, also have following point: because the particle of high specific gravity such as titanium dioxide is dispersed in low-gravity solution, therefore, the easy sedimentation of particle of high specific gravity such as this titanium dioxide is difficult to keep the stability of disperse state, and the repetition stability that information shows is poor.In addition, even make microcapsules, making cell size reach the microcapsules level, also only is to make above-mentioned shortcoming be difficult to show from the teeth outwards, but unresolved any substantive issue.

Method as the problems referred to above of bringing for the electrophoresis mode that solves the behavior of employing utilization in solution, proposition has such information display panel: after having enclosed display medium between two opposing substrates, or form the cell of isolating mutually by the next door, after being sealing into display medium in the cell, display medium is applied electric field and makes display medium move information such as display image.(for example, State of Zhao comes, other 3 people, and " new い ト Na one デ イ ス プ レ イ デ バ イ ス (I) ", on July 21st, 1999, Japanese iconology meeting annual general meeting (the 83rd) " Japan Hardcopy ' 99 " collection of thesis, reference is p.249-252).

The basic of their display mechanism is the surface charge of particle, for obtain to stablize, the demonstration of high definition, need the stable surface charge that keeps this particle.But surface charge is very unsettled, for example both decays because of environment such as humidity easily, changes because of contacting or rub with other materials easily again.In addition, if having any material to move or produce distortion on the particle, surface charge can change.The variation of these surface charges as above-mentioned display mechanism is expressed, is related to the variation of show state, has the long-term keeping because of information display panel, long-term use etc., and makes the show state problem of unstable.

Summary of the invention

The objective of the invention is to eliminate above-mentioned problem points, the display medium that provides a kind of and surface charge can be kept stable, can make information show state long-term stability such as image is with particle and use the information display panel of this particle.

Display medium of the present invention constitutes display medium with particle, this display medium is used for the display medium more than inclosure between two relative substrates is at least a, display medium is applied electric field and make display medium move the information display panel of information such as display image, at least one substrate is transparent in the above-mentioned opposing substrates, it is characterized in that, dispose material at particle surface with semi-conductor electricity characteristic.

In addition, as the preference of display medium of the present invention with particle, the material with semi-conductor electricity characteristic is the electron transport material; Material with semi-conductor electricity characteristic is the cavity conveying material; The surface of contact of at least one substrate in the particle surface with electron transport electrical characteristics and two the relative substrates is the relation of electric property ground rectification contact; The surface of contact of at least one substrate in the particle surface with cavity conveying electrical characteristics and two the relative substrates is the relation of electric property ground rectification contact; And have the particle of electron transport electrical characteristics and the particle that particle surface has the cavity conveying electrical characteristics, charged polarity difference separately with particle surface; Being configured in as the material on the particle surface of matrix is metal or metal oxide.

In addition, as the preference of display medium of the present invention with particle, if when the Fermi level of the substrate surface that it is Fb that particle surface has Fermi level in the surface that Fermi level in the surface of particle A of electron transport electrical characteristics is particle B with cavity conveying electrical characteristics of Fa, particle surface, contact with particle is Fs, be the relation of Fa＜Fs＜Fb; The charged characteristic that particle surface has the particle of electron transport electrical characteristics is a positive polarity; The charged characteristic that particle surface has the particle of cavity conveying electrical characteristics is a negative polarity; Particle is to constitute by using on electron transport material or the surface of cavity conveying coated materials as the particle of matrix.

In addition, as the preference of display medium of the present invention with particle, be that the Fermi level of Fc, particle surface is Fa, when the Fermi level of the substrate surface that contacts with particle is Fs, be the relation of Fc＜Fa＜Fs if particle surface has the Fermi level as the particle surface of matrix of electron transport electrical characteristics; Be that the Fermi level of Fc, particle surface is Fb, when the Fermi level of the substrate surface that contacts with particle is Fs, be the relation of Fc＞Fb＞Fs if particle surface has the Fermi level as the particle surface of matrix of cavity conveying electrical characteristics; Particle is that the monomer by electron transport material or cavity conveying material constitutes; Particle is by constituting electron transport material or cavity conveying dispersion of materials in resin.

In addition, display medium of the present invention constitutes display medium with particle, this display medium is used for the display medium more than inclosure between two relative substrates is at least a, display medium is applied electric field and make display medium move the information display panel of information such as display image, at least one substrate is transparent in the above-mentioned opposing substrates, it is characterized in that particle surface is the duplexer of semiconductor material.

In addition, as the preference of display medium of the present invention with particle, at least a particle surface is made of the electron transport material, and its lower floor is made of the cavity conveying material; Particle demonstrates electronegative characteristic; At least a particle surface is made of the cavity conveying material, and its lower floor is made of the electron transport material; Particle demonstrates the positively charged characteristic; Substrate is that ohmic properties contacts with particle surface.

In addition, information display panel of the present invention, display medium more than inclosure between two relative substrates is at least a, display medium is applied electric field and makes display medium move information such as display image, at least one substrate is transparent in the above-mentioned opposing substrates, it is characterized in that, use the display medium that constitutes with particle by the display medium of said structure as display medium.

Description of drawings

Fig. 1 (a) and (b) are respectively expressions with display medium of the present invention with the figure of particle as an example of the information display panel of display medium.

Fig. 2 (a) and (b) are respectively expressions with display medium of the present invention with the figure of particle as another example of the information display panel of display medium.

Fig. 3 (a) and (b) are respectively expression is used as display medium of the present invention the information display panel of display medium with particle the figure of an example again.

Fig. 4 is expression is used as display medium of the present invention one example of the next door shape in the information display panel of display medium with particle figure.

Fig. 5 is the figure of an example of confirmation method of rectification contact that is used for illustrating the present invention's semiconductor film.

Fig. 6 is the figure of an example of I-E characteristic of expression Ohmic contact that is used for illustrating the confirmation method of rectification contact shown in Figure 5.

Fig. 7 is the figure of an example of I-E characteristic of expression rectification contact that is used for illustrating the confirmation method of rectification contact shown in Figure 5.

Embodiment

At first, describe using by the basic structure of display medium of the present invention with the information display panel of the display medium of particle (below be also referred to as particle) formation.In information display panel of the present invention, apply electric field to being sealing into two display mediums between the opposing substrates.Along the direction of an electric field that is applied, charged display medium is subjected to the attraction of electric field force, Coulomb force etc., and the moving direction of display medium is switched according to the variation of the direction of an electric field that the switching owing to current potential causes, thereby the information of realization image etc. shows.Therefore, information display panel must be designed to that display medium moves equably, and stability can keep update displayed time the or the stability during display message continuously.At this, think the power on the particle that constitutes display medium of being applied to, except the power that attracts each other that produces by the Coulomb force between the particle, also have the Electronic Speculum image force, intermolecular force, liquid bridge power, gravity of itself and electrode or substrate etc.

Based on Fig. 1 (a) and (b)～Fig. 3 (a) and (b), the example of information display panel of the present invention is described.

At Fig. 1 (a), (b) in the example shown in, will be by the optical reflectivity that at least a above particle constitutes the display medium at least 2 kind or more 3 different (shown here is thewhite display medium 3W that is made of with the population of particle the display medium of white and theblack display medium 3B that is made of with the population of particle 3Ba the display medium of black) corresponding to by fromsubstrate 1 with charged characteristic, the electric field that 2 outsides apply, withsubstrate 1,2 vertically move, make observer's visible blackcolor display medium 3B and carry out black display, perhaps make the visiblewhite display medium 3W of observer and carry out white and show.In addition, in the example shown in Fig. 1 (b), on the example shown in Fig. 1 (a), betweensubstrate 1,2, for example cancellatenext door 4 is set and the formation cell.In addition, in Fig. 1 (b), omitted the next door that is positioned at the front side.

At Fig. 2 (a), (b) in the example shown in, will be by the optical reflectivity that at least a above particle constitutes the display medium at least 2 kind or more 3 different (shown here is thewhite display medium 3W that is made of with the population of particle the display medium of white and theblack display medium 3B that is made of with the population of particle the display medium of black) corresponding to by betweenelectrode 5 that is arranged atsubstrate 1 and theelectrode 6 that is arranged atsubstrate 2, applying the electric field that voltage produces with charged characteristic, withsubstrate 1,2 vertically move, make observer's visible blackcolor display medium 3B and carry out black display, perhaps make the visiblewhite display medium 3W of observer and carry out white and show.In addition, in the example shown in Fig. 2 (b), on the basis of the example shown in Fig. 2 (a), betweensubstrate 1,2, for example cancellatenext door 4 is set and the formation cell.In addition, in Fig. 2 (b), omitted the next door that is positioned at the front side.

In the example shown in Fig. 3 (a) and (b), a kind ofdisplay medium 3 with optical reflectivity and charging property that will be made of at least a above particle (shown here is thewhite display medium 3W that is made of with the population of particle the display medium of white) is corresponding to by applying the electric field that voltage produces between theelectrode 5 of being located atsubstrate 1 andelectrode 6, move along the direction parallel withsubstrate 1,2, make the visiblewhite display medium 3W of observer and carry out white to show, perhaps make the color ofvisible electrode 6 of observer orsubstrate 1 and the color ofshow electrode 6 or substrate 1.In addition, in the example shown in Fig. 3 (b), on the example shown in Fig. 3 (a), betweensubstrate 1,2, for example cancellatenext door 4 is set and the formation cell.In addition, in Fig. 3 (b), omitted the next door that is positioned at the front side.

The of the present invention the 1st is characterised in that being used for display medium uses with the particle of particle and have the material of semi-conductive electrical characteristics, thereby makes surface charge keep stable, obtains the information show state of the stable image etc. of high-contrast.

As preferred object lesson, use material with semi-conductive electrical characteristics for particle surface, the particle surface that is had nothing in common with each other by electrical characteristics, have electron transport and have the particle that the particle surface of the electrical characteristics of cavity conveying constitutes uses in the above-mentioned particle a certain particle separately or and uses above-mentioned particle according to the structure of information display panel.In addition, there are the relation of electric property ground rectification contact in these particle surfaces and at least one side's particle surface of contact in relative two substrates.Below, the action effect when using these materials describes.

As an example, there is the relation of electric property ground rectification contact in the surface of contact of at least one side's particle in the particle with the semi-conductive electrical characteristics of electron transport and relative two substrates.So-called rectification contact, when being meant the dissimilar substances contact, its electrical characteristics are not deferred to ohm's law and the contact that has directivity on the size of flow of charge.More along the electric charge that direction flows, contrary direction is mobile charge less.Is example with the cavity conveying semiconductor with contacting of metal, the pass of the two be the work function of the semi-conductive Fermi level＜metal of electron transport such concern the time, then for the rectification contact.

In the present invention, when the Fermi level that is the semi-conductive Fermi level of electron transport＜particle surface of contact such concern the time, then have rectification effect.When the surface of contact that contacts with particle (substrate) is negative potential, be contrary direction, therefore, the negative charge that flows into the electron transport semiconductor particle from surface of contact is less, when side's particle surface of contact (substrate) is positive potential, be suitable direction, therefore, the negative charge that flows to contact surface side from the electron transport semiconductor particle is more, band positive polarity in the particle.More than, be that example is illustrated with the electron transport semiconductor, when adopting the cavity conveying semiconductor, its characteristic only is and adopts the semi-conductive characteristic of electron transport opposite that phenomenon is identical.

At this, make particle properties and the electric charge that injects deposits the formation of particle inside in rectification effect in order to show better effect, need to give.In addition, must make the efficient of this iunjected charge also good.In order to reach this purpose, be metal or metal oxide by making surface as the particle of matrix, dispose electron transport or cavity conveying semiconductor material in its surface, can make these characteristics better.To adjusting tone with having disposed the display medium that these electron transport, two kinds of particles of cavity conveying material constitute from the teeth outwards, make contrast good, and between two electrode base boards that this display medium inclosure is relative, between electrode, apply electric field, thereby can show information such as preferable image.

Particle as matrix can be the particle that disposes metal or metal oxide on the surface, for example can be the particle that is made of metal monomer particle or metal oxide monomer.Perhaps, can be the particle that forms on the surface of particles such as resin with metal or metal oxide-coated, also can be the particle that forms on the surface of particles such as resin with metal or metal oxide topical application.The thickness of the semiconductor material on surface-coated (or local configuration is on surface) is not particularly limited, but consider the injection efficiency of electric charge, hope is that its thickness of film is below the 100 μ m, and the film of the following thickness of 50 μ m preferably is more preferably the film of the following thickness of 1 μ m.When being sealing into particle in the panel,, can suitably apply the particulate of particle diameter than little, the silicon dioxide of matrix particle or titanium dioxide etc. in order to improve flowability.

As the method for making of particle, as long as can show the above-mentioned electron transport or the electrical characteristics of cavity conveying, be not specially limited its method, but if illustration, preferred following method.Can point out such method: at first, prepare particle, apply the surface of this matrix particle with the semiconductor substance of electron transport or cavity conveying as matrix.As the method for surface-coated, can list following method: to carrying out evaporation or sputter carries out dry-coated method in the surface of matrix particle; Perhaps with in the semiconductor substance of matrix particle input is dissolved, fusion electron transport or cavity conveying and make the method for its drying, curing; Will the matrix particle drop in the particle stirring apparatus such as Henschel mixer and stir, therein the fixing method of the semiconductor substance of the electron transport of fusion or cavity conveying; And the semiconductor substance that makes electron transport or cavity conveying is scattered in other resins, this potpourri is coated on the method etc. on the surface of matrix particle with above-mentioned method.As other particle method for making, also can have the semiconductor substance of electron transport or cavity conveying and other resins are mixing and pulverize and obtain the method for particle, or with the semiconductor substance self of electron transport or cavity conveying as particle.

Wherein, when the surface-coated semiconductor material of matrix particle, the particle that the surface of preferably adopting the matrix particle has been covered by metal etc.The material of matrix particle is not particularly limited, and preferably uses common resins for universal use, inorganic material, metal material etc.In this case, preferably the matrix particle demonstrates Show Color, need have the particle of Visual Confirmation good color tone.

As an example of semiconductor material, at first,, can exemplify out silicon, germanium, adamas, selenium, tellurium etc. as the semiconductor substance of monomer.In addition, as compound semiconductor, can exemplify out gallium arsenide, gallium phosphide, indium arsenide, gallium aluminum arsenide, gallium aluminium indium arsenic, zinc sulphide, cadmium sulfide, cadmium selenide, cadmium telluride, silit etc.In addition, as oxide semiconductor, can exemplify out nickel oxide (II), cupric oxide (I), zinc paste, tin oxide (IV) etc.In addition, also include nitride-based semiconductor, sulfide semiconductor etc., and, also comprise the material that they are mixed and form.

In addition, as the lower-molecular substance in the organic semiconductor, can exemplify out the anthracene based compound, the violanthrone based compound, the porphyrin based compound, phthalocyanine dye based compound perylene based compound, the quinone based compound, the azo based compound, side's sour inner salt (Squarylium) based compound, Azulene salt (azlenium) based compound, the pyralium salt based compound, the cyanines based compound, the aromatic amine based compound, aromatic diamine based compound oxadiazole based compound oxazole based compound, the pyrazoline based compound, aromatic series methane series compound, the hydrazone based compound, carbazole based compound and these derivant etc.In addition, as the polymer substance in the organic semiconductor, can exemplify out polyacetylene, polyparaphenylene, polypyrrole, poly-thiophene phenol, polyaniline, poly-(to phenylacetylene) and these derivant etc.In addition, also be included in the semiconductor that impurity forms in the above-mentioned substance.

The selection of these materials is not particularly limited, but preferably selects Fermi level material in the above range, that have good stability, alternative costs material low, free of a burden to earth environment.In Fermi level, can reach iunjected charge expeditiously with the material that the energy difference of the Fermi level of electrode is bigger.

As the coating thickness that is coated on the surface, needs be suppressed to this thickness and not have blocked up along with thickness and degree that resistance rises, iunjected charge efficient reduces, normally below the 10 μ m, preferably below the 1 μ m.

The of the present invention the 2nd be characterised in that by particle surface be the duplexer of semiconductor material constitute display medium with particle and with this display medium with particle as the particle that constitutes display medium the configuration information display panel.

Using display medium of the present invention with in the information display panel of particle, the material as particle is contacted when mobile in panel can exemplify out other particles and substrate surface.In their whens contact, can produce that some are charged, but as its charged mechanism, and it is charged etc. to produce contact electrification, frictional electrification, stripping charge, conflict intricately.With these charged controls fully almost is impossible, but for wherein thinking to the bigger contact electrification of charged characteristic influence, can control with accuracy to a certain degree.

That is, utilize the electronic energy of each material differential, can when control example contacts as two materials, negative charge easily take place and move to which side.For example, can will be the cavity conveying material of carrier with the hole and be that the electron transport material of carrier is called effective material of controlling flow of charge with the electronics.The state that this two material has been engaged is called the pn knot, and is also general in diode, transistor etc.At this, consider when display medium is used particle that find such technology: make movement of electric charges have directivity by making up these materials, it is charged stably to keep particle.

Below, specifically giving an example describes.

Now, consider to form the structure of cavity conveying material at particle surface use electron transport material, in its lower floor.In this case, produce the pn knot on the composition surface of the two, at first carrier spreads to mutually opposite direction, carries out combination again.As a result, near the bonding land, produced the zone of having reduced many carriers, thereby, form from the electric field of electron transport material area to the cavity conveying material area.In other words, form negative charge easily from the electron transport material to cavity conveying material, the environment that promptly moves to inside from particle surface.On the contrary, since do not carry out negative charge from the cavity conveying material of particle inside to the moving of the electron transport material of particle surface, so the negative charge of putting aside on particle can be controlled to be constant direction.Therefore, under the situation of making such particle structure, can make particle have the character of stable easily carrying negative charge.

Then, when metal contacts with semiconductor,, be the ohmic properties contact sometimes because the relativeness of its energy level is the rectification contact sometimes.At this, the rectification contact can be positioned in metal and semi-conductive the contact, produce barrier and the contact of rectification takes place at contact site.In addition, ohmic properties contact may be defined as in metal and semi-conductive the contact, does not produce barrier and the contact that produces simple resistance at contact site.That is, utilize this characteristic, the substrate in the control information display panel, the structure of particle can be controlled the electric charge of putting aside on particle.

In the present invention, realize rectification characteristic herein, preferably carry out the contact condition that electric charge moves to particle surface from substrate easily in order to have the pn knot in particle inside.Therefore, contact with the particle surface ohmic properties, can make electric charge flow into particle effectively from substrate by making substrate.

On the contrary, when considering above-mentioned illustrative particle structure, if substrate becomes the relation that rectification contacts with particle surface, then owing to the relation of the barrier height of surface of contact, negative charge moves to substrate-side from the particle surface as the electron transport material easily.But, owing to formed negative charge in particle inside, therefore, can not obtain and make electric charge move the conformability that moves to a direction easily to the joint of particle medial movement, can not reach effective electric charge and flow into.

In particle structure, be under the situation of cavity conveying material, its inboard formation electron transport material at particle surface, except the electric charge difference, same phenomenon can be described.In this case, show the particle positively charged.

As the method for making of particle, as long as can show the above-mentioned electron transport or the electrical characteristics of cavity conveying, be not specially limited its method, but if illustration, preferred following method.Can point out such method: at first, prepare particle, apply the surface of this matrix particle with the semiconductor substance of electron transport or cavity conveying as matrix.As the method for surface-coated, can list following method: to carrying out evaporation or sputter carries out dry-coated method in the surface of matrix particle; Perhaps matrix particle input is dissolved, in the semiconductor substance of the electron transport of fusion or cavity conveying and make the method for its drying, curing; The matrix particle is put in the particle stirring apparatuss such as Henschel mixer and stirred, therein the fixing method of the semiconductor substance of the electron transport of fusion or cavity conveying; And the semiconductor substance that makes electron transport or cavity conveying is scattered in other resins, this potpourri is coated on the method etc. on the surface of matrix particle with above-mentioned method.As other particle method for making, also can have the semiconductor substance of electron transport or cavity conveying and other resins are mixing and pulverize and obtain the method for particle, or with the semiconductor substance self of electron transport or cavity conveying as particle.No matter adopt above-mentioned arbitrary method, all the stacked number according to duplexer repeats above-mentioned method.

Dispose from the teeth outwards in the particle of the semiconductor material that constitutes by electron transport material or cavity conveying material, as preferred disposition metal or metal oxide on the surface of the particle of matrix, for example can be the particle that constitutes by metal monomer particle or metal oxide monomer.Perhaps, can be with metal or metal oxide-coated on the surface of particles such as resin, also can be with metal or metal oxide topical application surface at particles such as resins.The thickness of the semiconductor material on surface-coated (or local configuration is on surface) is not particularly limited, but considers the injection efficiency of electric charge, and hope is that its thickness of very thin film is below the 100 μ m, preferably below the 50 μ m, is more preferably below the 1 μ m.When being sealing into particle in the panel,, can suitably apply the particulate of particle diameter than little, the silicon dioxide of matrix particle or titanium dioxide etc. in order to improve flowability.

The material of matrix particle is not particularly limited, and preferably uses common resins for universal use, inorganic material, metal material etc.In this case, preferably the matrix particle demonstrates Show Color, need have the particle of Visual Confirmation good color tone.

As being disposed at the example of display medium, at first,, can exemplify out silicon, germanium, adamas, selenium, tellurium etc. as the semiconductor substance of monomer with the semiconductor material of the surface of particle and substrate surface.In addition, as compound semiconductor, can exemplify out gallium arsenide, gallium phosphide, indium arsenide, gallium aluminum arsenide, gallium aluminium indium arsenic, zinc sulphide, cadmium sulfide, cadmium selenide, cadmium telluride, silit etc.In addition, as oxide semiconductor, can exemplify out nickel oxide (II), cupric oxide (I), zinc paste, tin oxide (IV) etc.In addition, also comprise nitride-based semiconductor, sulfide semiconductor etc., and, also comprise and contain the semiconductor that doping forms in them.

In addition, as the material in the organic semiconductor, can exemplify out anthracene based compound, violanthrone based compound, porphyrin based compound, phthalocyanine dye based compound, perylene based compound, quinone based compound, azo based compound, the sour inner salt based compound in side, Azulene salt based compound, pyralium salt based compound, cyanines based compound, aromatic amine based compound, aromatic diamine based compound, oxadiazole based compound, oxazole based compound, pyrazoline based compound, aromatic series methane series compound, hydrazone based compound, carbazole based compound and these derivant etc.In addition, as the polymer substance in the organic semiconductor, can exemplify out polyacetylene, polyparaphenylene, polypyrrole, poly-thiophene phenol, polyaniline, poly-(to phenylacetylene) and these derivant etc.In addition, also be included in the material that impurity forms in the above-mentioned substance.

As the coating thickness that is coated on the surface, needs be suppressed to this thickness and not have blocked up along with thickness and degree that resistance rises, iunjected charge efficient reduces, normally below the 10 μ m, preferably below the 1 μ m.

Below, describe for the basic structure of display medium of the present invention with particle (following also the abbreviation made particle).

Particle is preferably sphere.In particle, in resin, can comprise charge control agent, colorant, inorganic additive etc. as required as its principal ingredient samely.Below, example illustrates resin, charge control agent, colorant, other adjuvant.

Example as resin, can list urethane resin, urea resin, acrylic resin, vibrin, acrylated polyurethane resin, the acroleic acid polyurethane silicone resin, the acroleic acid polyurethane fluororesin, the acrylic acid fluororesin, silicone resin, the silicon Acrylote ketone resin, epoxy resin, polystyrene resin, styrene acrylic resin, polyolefin resin, butyral resin, permalon, melmac, phenolics, fluororesin, polycarbonate resin, polysulfone resin, polyether resin, polyamides etc. also can mix above-mentioned resin more than 2 kinds.Particularly consider that from the control and the adhesion aspect of substrate what be fit to is acrylated polyurethane resin, silicon Acrylote ketone resin, acrylic acid fluororesin, acroleic acid polyurethane silicone resin, acroleic acid polyurethane fluororesin, fluororesin, silicone resin.

For charge control agent, be not particularly limited, as negative charge controlling agent, can list oil-soluble dyes, quaternary ammonium compound, calixarene compound, boron-containing compound (diphenylglycollic acid boron complex), nitro imidazole derivatives of for example salicylic acid metal complex, containing metal azo dyes, containing metal (containing metallic ion or metallic atom) etc.As positive charge control agent, can list for example aniline black byestuffs, triphenyl methane compounds, quaternary ammonium compound, polyamino resin, imdazole derivatives etc.In addition, can also be with the resin of nitrogenous ring compound such as metal oxide, pyridine such as ultra micron silicon dioxide, ultra micron titanium dioxide, ultra micron aluminium oxide and derivant thereof or salt, various organic pigment, fluorine-containing, chlorine, nitrogen etc. etc. as charge control agent.

As colorant, can use pigment, dyestuff various of all kinds as following illustrative organic or inorganic.

As black colorant, can use carbon black, cupric oxide, manganese dioxide, nigrosine, activated charcoal etc.

As blue colorant, the C.I. pigment blue 15 is arranged: 3, the part chloride of C.I. pigment blue 15, dark purple, cobalt blue, alkali blue lake, Victoria blue color lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue, fast sky blue, indanthrene blue BC etc.

As red stain, have that colcother, cadmium red, red lead, mercuric sulphide, cadmium, permanent red 4R, lithol red, pyrazolone red, Wo Qiuge are red, calcium salt, C lake red CAN'T D, brilliant carmine 6B, eosine lake, rhodamine color lake B, alizarine lake,bright carmine 3B, C.I.paratonere 2 etc.

As yellow colorants, chrome yellow, zinc yellow, cadmium yellow, yellow iron oxide, inorganic permanent yellow, nickel titanium yellow, navel orange Huang, naphthol yellow S, hansa yellow G, hansa yellow 10G, benzidine yellow G, benzidine yellow G R, quinoline yellow lake, permanent yellow NCG, tartrazine lake, C.I. pigment Yellow 12 etc. are arranged.

As green colourant, chrome green, chromium oxide, pigment green B, C.I. pigment Green 7, peacock green color lake, final yellowish green G (final yellow green G) etc. are arranged.

As orange colorant, red chrome yellow, molybdate orange, permanent orange GTR, pyrazolone orange, fast orange (vulcan orange), indanthrene brilliant orange RK, Benzidine orange G, indanthrene brilliant orange GK, C.I. pigment orange 31 etc. are arranged.

As violet colorant, manganese violet, Fast violet B, methyl violet color lake etc. are arranged.

As white color agents, zinc paste, titanium dioxide, stibium trioxide, zinc sulphide etc. are arranged.

As extender pigment, there are ground barium sulfate, barium carbonate, clay, silicon dioxide, white carbon, talcum, aluminium oxide white etc.In addition, as various dyestuffs such as alkalescence, acidity, dispersion, direct dyess, nigrosine, methylene blue, rose-red, quinoline yellow, ultramarine blue etc. are arranged.

As the example of mineral-type adjuvant, can list that titanium dioxide, zinc paste, zinc sulphide, antimony oxide, lime carbonate, white lead, talcum, silicon dioxide, calcium silicate, aluminium oxide are white, cadmium yellow, cadmium red, cadmium orange, titan yellow, dark purple, ultramarine, cobalt blue, cobalt green, cobalt violet, iron oxide, carbon black, the manganese ferrite is black, the cobalt ferrite is black, copper powder, aluminium powder etc.

These pigment and mineral-type adjuvant can use separately or multiple being used in combination.Wherein, especially as the preferred carbon black of black pigment, as the preferred titanium dioxide of Chinese white.

Mix above-mentioned colorant, can make the display medium particle of desired color.

In addition, the mean grain size d of particle used in the present invention (0.5) is preferably at scope and the uniformity of 0.1～20 μ m.If mean grain size d (0.5) greater than this scope, then lacks the vividness on showing, if less than this scope, then the aggregation force between the particle becomes excessive, therefore can be to the mobile obstruction of bringing of display medium.

In addition, in the present invention, about the size distribution of each particle, the span of the size distribution shown in the following formula (Span) less than 5, preferred less than 3.

Span＝(d(0.9)-d(0.1))/d(0.5)

(wherein, d (0.5) is the grain diameter value of representing with μ m, 50% bigger in the particle than it, and 50% is littler than it; D (0.1) is the grain diameter value of representing with μ m, and particle diameter is 10% at the ratio of this particle below numerical value; D (0.9) is the grain diameter value of representing with μ m, and particle diameter is 90% at the ratio of this particle below numerical value.)

By span Span is in the scope below 5, the consistent size of each particle can realize moving uniformly of display medium.

In addition, for the relation of each particle, the d (0.5) that importantly has the particle of minimum diameter in employed particle is below 50, is preferably below 10 with respect to the ratio of the d (0.5) of the particle with maximum gauge.Even if make size distribution span Span little, also owing to be that the particle that charged characteristic differs from one another moves each other in the opposite direction, therefore what be fit to is that both sides' particle size is approaching, and both sides' particle can easily move according to equivalent round about, and this just requires above-mentioned scope.

In addition, above-mentioned size distribution and particle diameter can be tried to achieve by laser diffraction/scattering method etc.If to particle-irradiation laser as determination object, then can produce the light intensity distributions pattern of the diffraction/scattered light in space, because there are corresponding relation in this light intensity pattern and particle diameter, therefore can measure particle diameter and size distribution.

At this, particle diameter among the present invention and size distribution are distributed by volume reference and obtain.Specifically, can use Mastersizer2000 (MalvernInstruments Ltd.) mensuration machine, in stream of nitrogen gas, drop into particle, use subsidiary analysis software (being distributed as the software on basis with the volume reference that adopts the Mie theory), measure particle diameter and size distribution.

Display medium obviously depends on its condition determination with the carried charge of particle, display medium in the Given information display panel with the carried charge of particle depend on the initial strip electric weight substantially, with the contacting of next door, with the contacting of substrate, along with charge decay, the especially display medium in elapsed time are determinatives with the saturation value of the charged behavior of particle.

The inventor has carried out the result that studies intensively, finds can estimate the scope of display medium with the suitable charged characteristic value of particle by using identical carrier particle to measure the carried charge of the particle that display medium uses in blowing out (blowoff) method.

In addition, will be applied to by the display medium that display medium constitutes with particle under the situation of dry type information display panel, it is important that the gas of the gap of display medium between the encirclement substrate is managed, and it helps to improve exhibit stabilization.Specifically, for the humidity of the gas of gap, the relative humidity under 25 ℃ is that 60%RH is following, to be preferably below the 50%RH be important.

In Fig. 1 (a) and (b)～Fig. 3 (a) and (b), this gap is meant gas part hermetic unit, that so-called display medium contacted of occupying part (being provided with under the situation in next door), information display panel of occupying part,next door 4 that deductselectrode 5,6 (electrode being arranged under the situation of substrate inboard),display medium 3 from be clipped in the part between opposingsubstrates 1, thesubstrate 2.

The gas of gap is so long as in above-mentioned humidity range, its kind just without limits, what be fit to is dry air, drying nitrogen, dry argon gas, dry helium gas, dry carbon dioxide, dry methane etc.This gas must be enclosed under the condition that keeps its humidity in the information display panel, for example under the humidity environment of regulation, carry out the filling of display medium, the assembling of information display panel etc., in addition, apply in order to prevent that encapsulant, encapsulating method that moisture is invaded from the outside from being important.

As substrate in the information display panel of object of the present invention and the interval between the substrate, as long as display medium can move, can to keep contrast just passable, be adjusted into 10～500 μ m usually, be preferably 10～200 μ m.

The volume occupation rate of display medium is preferably 5～70% in the space between the opposing substrates, and more preferably 5～60%.Under 70% the situation of surpassing, to the mobile generation obstacle of display medium, under the situation of less than 5%, it is unintelligible that contrast becomes easily.

Below, each member that constitutes as the information display panel of object of the present invention is described.

About substrate, at least one substrate is to have above-mentioned characteristic of the present invention, and at least one substrate is thetransparency carrier 2 that can observe the color ofdisplay medium 3 from panels outside, and its suitable material is transmission of visible light height and the good material ofthermotolerance.Substrate 1 can be transparent also can be opaque.Baseplate material is carried out illustrative words, can list polymer sheets such as polyethylene terephthalate, Polyethylene Naphthalate, polyethersulfone, tygon, polycarbonate, polyimide, esters of acrylic acid, or metal sheet such have a flexible material; And glass, quartz etc. do not have flexible inorganic sheet.The thickness of substrate is preferably 2～5000 μ m, further is suitably for 5～2000 μ m, if thin excessively, then is difficult to keep intensity, substrate distance homogeneity, if thicker than 5000 μ m, then is not suitable as slim information display panel.

Electrode when on information display panel electrode being set forms material, can metal species such as aluminium, silver, nickel, copper, gold be arranged illustration; Or conducting metal oxide class such as tin indium oxide (ITO), indium oxide, conductive tin oxide, tin-antimony oxide (ATO), electroconductive zinc oxide; Electroconductive polymer classes such as polyaniline, polypyrrole, polythiophene can suitably be selected to use.Formation method as electrode, can adopt by sputtering method, vacuum vapour deposition, CVD (chemical vapor deposition) method, rubbing method etc. to make above-mentioned illustrative material form the method for film like, perhaps adopt by conductive agent being mixed into the method that is coated with in solvent or the synthetic resin adhesive.The electrode that is arranged on visual side (display surface side) substrate must be transparent, but the electrode that is arranged on the rear side substrate needs not to be transparent.Can be fit to use the above-mentioned material that all can form the electric conductivity of pattern in either case.In addition,, be suitably for 3～1000nm, be preferably 5～400nm as long as the thickness of electrode can be guaranteed electric conductivity, not hinder transmitance.The material that is arranged on the electrode on the rear side substrate can be identical with the above-mentioned electrode that is arranged on the display surface side group plate with thickness etc., but need not to be transparent.In addition, can superpose direct current or interchange of the external voltage input during this situation.

About being arranged on thenext door 4 on the substrate as required, its shape can be according to the kind of the display medium that is used to show, carry out suitably optimization setting, limited without exception, but the width in next door can be adjusted into 2～100 μ m, be preferably 3～50 μ m, and the height in next door can be adjusted into 10～500 μ m, be preferably 10～200 μ m.In addition, as shown in Figure 4, by the cell that the next door that is made of these ribs forms, observe from the base plan direction, illustration has quadrilateral, triangle, wire, circle, hexagon; As its configuration, can clathrate, cellular or mesh-shape be arranged illustration.Reasonable is to dwindle as far as possible to be equivalent to can increase the sharpness of show state like this from showing the part (area of cell frame part) of cross section, the appreciable next door of side part.

Embodiment

Below, embodiment is shown, comparative example is described more specifically the present invention.But the present invention is not limited by each following example.

As shown below, make the information display panel ofembodiment 1～8,11～13, comparative example 1～3,11～12, obtain the various characteristics of the information display panel of producing and compare.At first, in each following example, the assay method of the various mensuration of the confirmation method of the rectification contact that utilized and information display panel is described, then each example is described.

The confirmation method of rectification contact

The contact of rectification I-E characteristic is by inquiry implemented.At first, as shown in Figure 5,, Al electrode, Au electrode simultaneously are set, ITO electrode, Al electrode, Au electrode are set and carry out stackedly, produce working sample at its another side at it across semiconductor film.The pass of the work function of electrode material is Al＜ITO＜Au.About sample, electrode is adopted the vapour deposition method film forming, adopt vapour deposition method or rotation to apply the coating liquid that is dissolved in arbitrary solvent to semiconductor film and carry out film forming.

And, when between to Al-Al, applying voltage, I-E characteristic is shown in the example of Fig. 6, the expression Ohmic contact, when applying voltage between Al-ITO, I-E characteristic shown in the example of Fig. 7, expression rectification contact, and the anodal polarity bias of ITO is when the direction, and this semiconductor film can be described as becomes the semiconductor substance of carrying property with ITO rectification contacting electronic.On the other hand, when between to Au-Au, applying voltage, I-E characteristic is shown in the example of Fig. 6, the expression Ohmic contact, when applying voltage between Al-ITO, I-E characteristic shown in the example of Fig. 7, expression rectification contact, and the negative pole polarity bias of ITO is when the direction, and this semiconductor film can be described as the semiconductor substance that becomes the cavity conveying that contacts with the ITO rectification.

The assay method of various characteristics

Mean particle diameter d (0.5), particle diameter Span to above-mentioned example measure.After cutting off particle, utilize SEM to observe, measure the coating thickness of the superficial layer ofembodiment 1,2,5～8, embodiment 11～13, comparative example 2,3, comparative example 11,12, utilize TEM to observe, measure the coating thickness of the superficial layer ofembodiment 3,4.Repeating to open panel behind 100 display updates with information display panel, the particle that faraday's meter of use aspiration-type attracts to be attached on the display panel substrate is measured charging property and carried charge.By the initial show state of Visual Confirmation and applied ± and 150V and repeat the show state behind the display update 5,000,000 times, come the comparison contrast.Also by the initial show state of Visual Confirmation and applied ± 150V and repeat the show state behind the display update 5,000,000 times, come the comparison display quality.

Embodiment 1

According to following table 1, prepare to have applied theparticle 1 and theparticle 2 on resin particle surface with organic semiconductor.Useready particle 1 andparticle 2, inclosure has between two ito substrates of electrode respectively, produces information display panel.The composite rate that is adjusted toparticle 1 andparticle 2 beparticle 1 andparticle 2 respectively for identical weight, be 30 capacity % with these particle-filled loadings between substrate.

Ecbatic in following table 1.

Table 1

Embodiment 2

According to following table 2, preparation has carried out using after thesurface treatment particle 1 and theparticle 2 of organic semiconductor coating surface to resin surface with metal oxide.In addition, intersperse among the matrix particle shown in the table 2 on the flat board equably, from top by laser ablation to after becoming display medium and having implemented surface treatment with the resin particle surface of the particle of particle matrix, make the incomplete resin particle minute movement of processing and the face of being untreated is exposed to the surface, similarly carry out surface treatment again, come particle surface is carried out vapor deposition treatment equably by carrying out such surface treatment procedure repeatedly.Then, useready particle 1 andparticle 2, enclose similarly to Example 1 between the ito substrate, produce information display panel.Ecbatic in following table 2.

Table 2

Embodiment 3

According to following table 3, prepare the matrix particle surface have been carried outparticle 1 andparticle 2 that sputter is handled with metaloxide.Ready particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 1, produced information display panel.Ecbatic in following table 3.

Table 3

Embodiment 4

According to following table 4, prepare by semiconductormonomer constituent particle 1 and particle 2.Ready particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 1, produced information display panel.Ecbatic in following table 4.

Table 4

Embodiment 5

According to following table 5, preparation is with semiconductor material and resin is mixing and their are pulverizedparticle 1 and theparticle 2 that carries out classification and get.Ready particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 1, produced information display panel.Ecbatic in following table 5.

Table 5

Embodiment 6

According to following table 6, so prepareparticle 1 andparticle 2, theparticle 1 of present embodiment is identical with theparticle 1 ofembodiment 1 record, and theparticle 2 of present embodiment is to add adjuvant in theparticle 2 ofembodiment 1 record.Adding adjuvant is by the adjuvant shown in the input table 6, and makes its even dispersion with Henschel mixer, carries out thereby adjuvant is attached on the particlesurface.Resulting particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 1, produced information display panel.Ecbatic in following table 6.

Table 6

Embodiment 7

According to following table 7, so prepareparticle 1 andparticle 2, theparticle 1 of present embodiment is identical with theparticle 1 ofembodiment 1 record, and theparticle 2 of present embodiment uses the particle that does not have semi-conductive electrical characteristics on thesurface.Resulting particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 1, produced information display panel.Ecbatic in following table 7.

Table 7

Embodiment 8

According to following table 8, so prepareparticle 1 andparticle 2, theparticle 1 of present embodiment is identical with theparticle 1 ofembodiment 2 records, and theparticle 2 of present embodiment uses the particle that does not have semi-conductive electrical characteristics on thesurface.Resulting particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 1, produced information display panel.Ecbatic in following table 8.

Table 8

Comparative example 1

According to following table 9, prepare inembodiment 1, not carry out theparticle 1 andparticle 2 of semiconductorprocesses.Ready particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 1, produced information display panel.Ecbatic in following table 9.

Table 9

Comparative example 2

According to following table 10, prepare to have appliedparticle 1 and theparticle 2 that becomes the ohmic properties contact as the surface of the resin particle of matrix with organic semiconductor.Ready particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 1, produced information display panel.Ecbatic in following table 10.

Table 10

Comparative example 3

According to following table 11, prepare the surface of the resin surface that becomes matrix have been carried out after the surface treatment with organic semiconductor coating surface Fermi level that form,particle structure particle 1 and theparticle 2 opposite with the embodiment of the invention with metal oxide.The matrix particle is interspersed among on the flat board equably, the particle surface that becomes matrix has been implemented surface treatment from top by laser ablation.Then, make the particle minute movement and the face of being untreated is exposed to the surface, similarly carry out surface treatment again.Come vapor deposition treatment is equably carried out on the surface of matrix particle by carrying out such surface treatment repeatedly.Then, useready particle 1 andparticle 2, enclose similarly to Example 1 between the ito substrate, produce information display panel.Ecbatic in following table 11.

Table 11

From above result as can be known, compare according to the comparative example 1～3 outside the embodiments of theinvention 1～8 and the scope of the invention, it is all good initially to reach 5,000,000 carried charge, contrast, display qualities after the demonstration.In addition, in an embodiment,embodiment 6 can move with low driving voltage.

Embodiment 11

According to following table 12, prepareparticle 1 andparticle 2, thisparticle 1 is to use Cu₂O carries out surface treatment, applied that semiconductor layer forms, surface thereon then and be made of duplexer the particle that becomes matrix, and thisparticle 2 is with ZnO the particle that becomes matrix to be carried out surface treatment, applied that semiconductor layer forms, surface thereon then and be made of duplexer.The matrix particle is interspersed among on the flat board equably, carry out Cu from top by laser ablation₂The surface treatment of O and ZnO.Then, make the particle minute movement and the face of being untreated is exposed to the surface, similarly carry out surface treatment again.Come particle surface is carried out vapor deposition treatment equably by carrying out such surface treatment repeatedly.Then, useready particle 1 andparticle 2, enclose between two ito substrates, produce information display panel.The composite rate that is adjusted toparticle 1 andparticle 2 beparticle 1 andparticle 2 respectively for identical weight, be 30 capacity % with these particle-filled loadings between substrate.Ecbatic in following table 12.

Table 12

Embodiment 12

According to following table 13, so prepareparticle 1 andparticle 2, theparticle 2 of present embodiment is identical with theparticle 2 of embodiment 11 records, and theparticle 1 of present embodiment is to add adjuvant in theparticle 1 of embodiment 11 records.Adding adjuvant is by the adjuvant shown in the input table 13, and makes its even dispersion with Henschel mixer, carries out thereby adjuvant is attached on the particle surface.Then,ready particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 11, produced information display panel.Ecbatic in following table 13.

Table 13

Embodiment 13

According to following table 14, so prepareparticle 1 andparticle 2, theparticle 1 of present embodiment is identical with theparticle 1 of embodiment 11 records, and theparticle 2 of present embodiment is the particle that the semiconductor layer laminate materials is not set at particlesurface.Ready particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 11, produced information display panel.Ecbatic in following table 14.

Table 14

Comparative example 11

According to following table 15, prepare in embodiment 11, not carry out theparticle 1 andparticle 2 of semiconductorprocesses.Ready particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 11, produced information display panel.Ecbatic in following table 15.

Table 15

Comparative example 12

According to following table 16, prepareparticle 1 andparticle 2, the surperficial duplexer of thisparticle 1 all is to be made of the electron transport material, the surperficial duplexer of thisparticle 2 all is to be made of the cavity conveying material.Ready particle 1 andparticle 2 are enclosed between the ito substrate similarly to Example 11, produced information display panel.Ecbatic in following table 16.

Table 16

From above result as can be known, compare according to the comparative example 11,12 that the embodiments of the invention 11～13 and the scope of the invention are outer, it is all good initially to reach 5,000,000 carried charge, contrast, display qualities after the update displayed.In addition, in an embodiment, embodiment 12 can drive with low driving voltage and carry out work.

Utilizability on the industry

Display medium of the present invention is used as the information display panel of display medium with particle, be applicable to notebook-PC, PDA, portable phone, the display part of the removable machine such as portable terminal, e-book, the Electronic Paper such as electronic newspaper, billboard, placard, the notice boards such as blackboard (blank), desk top computer, household appliances, the display part of Automobile Products etc., point card (point card), the card display part of IC-card etc., e-advertising, information board, electronics POP (Point of presence, Point of Purchase advertising), the electronics price tag, the electronics inventory tag, electronic music, the display part of RF-ID equipment etc.

Claims (7)

1. display medium particle, be used for the display medium more than inclosure between two relative substrates is at least a, the display medium that is made of with particle described display medium is applied electric field and make display medium move the information display panel of information such as display image, at least one substrate is transparent in the above-mentioned opposing substrates, it is characterized in that

The surface of particle is the duplexer of semiconductor material.

2. display medium particle according to claim 1 is characterized in that particle surface is made of the electron transport material, and its lower floor is made of the cavity conveying material.

3. display medium particle according to claim 2 is characterized in that particle demonstrates electronegative characteristic.

4. display medium particle according to claim 1 is characterized in that particle surface is made of the cavity conveying material, and its lower floor is made of the electron transport material.

5. display medium particle according to claim 4 is characterized in that particle demonstrates the positively charged characteristic.

6. according to each described display medium particle in the claim 1～5, it is characterized in that substrate is that ohmic properties contacts with particle surface.

7. information display panel, display medium more than inclosure between two relative substrates is at least a applies electric field and makes display medium move information such as display image display medium, and at least one substrate is transparent in the above-mentioned opposing substrates, it is characterized in that

The display medium that use is made of with particle each described display medium in the claim 1～6 is as display medium.

Images